package com.gulimall.cart.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.utils.R;
import com.atguigu.common.vo.UserInfoTo;
import com.gulimall.cart.feign.ProductFeignService;
import com.gulimall.cart.interceptor.CartInterceptor;
import com.gulimall.cart.service.CartService;
import com.gulimall.cart.vo.Cart;
import com.gulimall.cart.vo.CartItem;
import com.gulimall.cart.vo.SkuInfoVo;
import io.netty.util.internal.StringUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.BoundHashOperations;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.math.BigDecimal;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.stream.Collectors;

@Service
public class CartServiceImpl implements CartService {

    @Autowired
    StringRedisTemplate redisTemplate;

    @Autowired
    ProductFeignService productFeignService;

    @Autowired
    ThreadPoolExecutor executor;


    private final String CART_PREFIX="gulimall:cart";

    @Override
    public CartItem addToCart(Long skuId, Integer num) throws ExecutionException, InterruptedException {
        BoundHashOperations<String, Object, Object> cartOps = getCartOps();
        String res = (String) cartOps.get(skuId.toString());
        if(StringUtil.isNullOrEmpty(res)){
            CartItem cartItem = new CartItem();

            CompletableFuture<Void> getSkuInfoTask = CompletableFuture.runAsync(() -> {
                R info = productFeignService.info(skuId);
                if (info.getCode() == 0) {
                    SkuInfoVo skuInfo = (SkuInfoVo) info.getData("skuInfo", new TypeReference<SkuInfoVo>() {
                    });
                    cartItem.setCheck(true);
                    cartItem.setCount(num);
                    cartItem.setImage(skuInfo.getSkuDefaultImg());
                    cartItem.setTitle(skuInfo.getSkuTitle());
                    cartItem.setSkuId(skuId);
                    cartItem.setPrice(skuInfo.getPrice());
                }
            }, executor);

            CompletableFuture<Void> getSkuSaleAttrValues = CompletableFuture.runAsync(() -> {
                List<String> values = productFeignService.getSkuSaleAttrValue(skuId);
                cartItem.setSkuAttr(values);
            }, executor);

            CompletableFuture.allOf(getSkuInfoTask,getSkuSaleAttrValues).get();
            String s = JSON.toJSONString(cartItem);
            cartOps.put(skuId.toString(),s);
            return cartItem;
        }else {
            //购物车有此商品，修改数量
            CartItem cartItem = JSON.parseObject(res, CartItem.class);
            cartItem.setCount(cartItem.getCount()+num);

            cartOps.put(skuId.toString(),JSON.toJSONString(cartItem));
            return cartItem;
        }
    }

    @Override
    public CartItem getCartItem(Long skuId) {

        BoundHashOperations<String, Object, Object> cartOps = getCartOps();
        String str = (String) cartOps.get(skuId.toString());
        CartItem cartItem = JSON.parseObject(str, CartItem.class);
        return cartItem;
    }

    @Override
    public Cart getCart() throws ExecutionException, InterruptedException {
        Cart cart = new Cart();
        UserInfoTo userInfoTo = CartInterceptor.threadLocal.get();
        if(userInfoTo.getUserId()!=null){
            //1、登录
            String cartKey = CART_PREFIX + userInfoTo.getUserId();
            //2、如果临时购物车的数据还没有进行合并【合并购物车】
            String tempCartKey = CART_PREFIX + userInfoTo.getUserKey();
            List<CartItem> tempCartItems = getCartItems(tempCartKey);
            if(tempCartItems != null){
                //临时购物车有数据，需要合并
                for (CartItem item : tempCartItems) {
                    addToCart(item.getSkuId(), item.getCount());
                }
                //清除临时购物车的数据
                clearCart(tempCartKey);
            }
            //3、获取登陆后的购物车数据【包含合并过来的临时购物车的数据，和登录后的购物车的数据】
            List<CartItem> cartItems = getCartItems(cartKey);
            cart.setItems(cartItems);

        }else {
            //2、没登录
            String cartKey = CART_PREFIX + userInfoTo.getUserKey();
            List<CartItem> cartItems = getCartItems(cartKey);
            cart.setItems(cartItems);
        }
        return cart;
    }

    @Override
    public void clearCart(String cartKey) {
        redisTemplate.delete(cartKey);
    }

    @Override
    public void checkItem(Long skuId, Integer check) {
        BoundHashOperations<String, Object, Object> cartOps = getCartOps();
        CartItem cartItem = getCartItem(skuId);
        cartItem.setCheck(check==1?true:false);
        String s = JSON.toJSONString(cartItem);
        cartOps.put(skuId.toString(),s);
    }

    @Override
    public void changeItemCount(Long skuId, Integer num) {
        CartItem cartItem = getCartItem(skuId);
        cartItem.setCount(num);

        BoundHashOperations<String, Object, Object> cartOps = getCartOps();
        cartOps.put(skuId.toString(),JSON.toJSONString(cartItem));
    }

    @Override
    public void deleteItem(Long skuId) {
        BoundHashOperations<String, Object, Object> cartOps = getCartOps();
        cartOps.delete(skuId.toString());
    }

    @Transactional
    @Override
    public List<CartItem> getUserCartItems() {

        UserInfoTo userInfoTo = CartInterceptor.threadLocal.get();
        if(userInfoTo.getUserId() == null){
            return null;
        }else {
            String cartKey = CART_PREFIX + userInfoTo.getUserId();
            List<CartItem> cartItems = getCartItems(cartKey);

            //获取所有被选中的购物项
            List<CartItem> collect = cartItems.stream().filter(item -> {
                return item.getCheck();
            }).map(temp->{
                R price = productFeignService.getPrice(temp.getSkuId());
                if(price.getCode() == 0){
                    String data = (String) price.get("data");
                    //TODO 1、更新为最新价格
                    temp.setPrice(new BigDecimal(data));
                }
                return temp;
            }).collect(Collectors.toList());
            return collect;
        }
    }

    private List<CartItem> getCartItems(String cartKey) {
        BoundHashOperations<String, Object, Object> hashOps = redisTemplate.boundHashOps(cartKey);
        List<Object> values = hashOps.values();
        if(values!=null && values.size()>0){
            List<CartItem> collect = values.stream().map(obj -> {
                String str = (String) obj;
                CartItem cartItem = JSON.parseObject(str, CartItem.class);
                return cartItem;
            }).collect(Collectors.toList());
            return collect;
        }
        return null;
    }

    private BoundHashOperations<String, Object, Object> getCartOps() {
        UserInfoTo userInfoTo = CartInterceptor.threadLocal.get();
        String cartKey = "";
        if(userInfoTo.getUserId() != null){
            //gulimall:cart:1
            cartKey = CART_PREFIX + userInfoTo.getUserId();
        }else {
            cartKey = CART_PREFIX + userInfoTo.getUserKey();
        }
        BoundHashOperations<String, Object, Object> operations = redisTemplate.boundHashOps(cartKey);
        return operations;
    }




}
